A new kid-derived game of late is helmet racing. You wear your bike helmet and race each other in circles around the house. There don't appear to be any apparent winners or losers as the racers begin when they feel like it and all chant, "I'm the fastest. I'm the fastest." Great for a pre-bedtime tire out session. Here is a tiny helmet race clip. It would have been longer but I ran out of memory on the camera. ;)